Cable Connection not being created between Arista switches and Hosts

Products

• VMware Smart Assurance

Issue/Introduction

Symptoms:


Cable connections are not being built during discovery for connections between Arista switches and some Hosts and other devices.

Environment

VMware Smart Assurance - SMARTS

Cause

In this case, the Host did not support LLDP neighbor protocol.  Since there was no neighbor protocol to use, discovery was forced to use the industry standard bridging protocol to try to build connections.  Unfortunately for many of the Arista switches, this information is not populated in their MIB.  This causes the discovery to fail to find bridging information that would allow the cable connection to be built.

Resolution

The current work around is to add a line to the Arista certification by essentially creating a field certification for affected Arista devices.  I will use .1.3.6.1.4.1.30065.1.3011.7280.3714.72 as an example.

The default certification for this device is:

#  Arista Arista 7280SE-64
.1.3.6.1.4.1.30065.1.3011.7280.3714.72 {
    TYPE = Switch
    VENDOR = Arista
    MODEL = Arista-7280SE-64
    CERTIFICATION = CERTIFIED
    CONT = Arista-Switch
    HOSTRESRCS = MIB2
    VLAN = AristaDot1q
    NEIGHBOR = LLDP
 
INSTRUMENTATION:
    Environment                         = AristaEntityFRU:DeviceID
    Card-Fault                          = EntityState:DeviceID
    Interface-Fault                     = MIB2
    Interface-Performance               = MIB2
    Port-Fault                          = MIB2
    Port-Performance                    = MIB2
}

By adding the option 'BRIDGE = Dot1q', we can add the required functionality to build many of these connections.  The modified certification will look like this:

#  Arista Arista 7280SE-64
.1.3.6.1.4.1.30065.1.3011.7280.3714.72 {
    TYPE = Switch
    VENDOR = Arista
    MODEL = Arista-7280SE-64
    CERTIFICATION = CERTIFIED
    CONT = Arista-Switch
    BRIDGE=Dot1q <------------ Added
    HOSTRESRCS = MIB2
    VLAN = AristaDot1q
    NEIGHBOR = LLDP
 
INSTRUMENTATION:
    Environment                         = AristaEntityFRU:DeviceID
    Card-Fault                          = EntityState:DeviceID
    Interface-Fault                     = MIB2
    Interface-Performance               = MIB2
    Port-Fault                          = MIB2
    Port-Performance                    = MIB2
}